1. Field of the Invention
The present invention relates generally to an image handling apparatus, and more particularly to an image scanner and to an image forming apparatus both for transferring data to and from an external host apparatus via an interface.
2. Description of the Prior Art
A computer is generally operatively connected to several peripheral devices such as, for example, a magnetic disc, a magnetic tape, a printer or the like. Recently, a small computer system interface (SCSI) is standardized as an interface means for carrying out high-speed data transfer. Through the standardization, the SCSI is in wide practical use today as an interface for various computers.
By virtue of marked improvement in performance of small computers, e.g. workstations, the development from character codes to bit-map data, which has hitherto been carried out in a printer, tends to be carried out in the computer using outline font data which the computer has. Whereas the technique of developing, for example, fonts to the bit-map data in the computer has advantages in adding other fonts, the use of the SCSI is inevitably required for high-speed data transfer because the quantity of data to be transferred from the computer to the printer is increased.
In applications where an image scanner or an image forming apparatus is connected to an SCSI of a computer employed as a host computer, and parameter setting for such apparatus or image data transfer is carried out by the computer, the computer is required to have a software "device driver" for the apparatus connected thereto.
Because image scanners or image forming apparatus are not standardized in kind of parameters which can be set or in functions, the device driver therefor is not generally contained in an operating system (OS) of the computer. Accordingly, it is necessary to prepare the device driver for the image scanner or the image forming apparatus connected to the host computer.
Under the present conditions discussed above, however, in order to enable a certain image scanner or image forming apparatus to be connected to any one of various types of host computers, it is necessary to prepare a device driver for each type of host computer. As a result, the problem arises that the preparation of the device driver requires much labor and increases costs.